I don't know how to do can you guys help me pls

What is the shape of the height and weight distribution

Find the condition that the zeros of the polynomial f(x) = x^3+3px^2+3px+r may be in a.p.

Astudent must have an average on five test that is greater than it equal to 80% but less than 90% to receive a final grade of b. devon's greades on the first four test were 78% 62% 91% and 80% what range if grades on the fifth test would give him a b in the course? ( assuming the highest grade is 100%)